The report describes studies of individual and team decision making in complex command, control and communication systems involving man machine and computer regulated interaction. The most recent advance is a comprehensive team decision system able to exteriorise normally hidden conceptual operations as behavioural records. The system has training, testing and operational applications. It incorporates an on line, novel concept, interrogation system, records for which (together with logging the condition of a space environment) provide indices of decision making style and performance which are compared with data from (also novel) tests for learning style. The system also incorporates a computer implemented planning and representation method as well as an environment in which the decision process is instituted by essential bifurcations. The method is a micro-behavioural conversation, based on conversation theory, from the conversation laboratory studies.